In recent years, as performances and functions of a digital information apparatus such as personal computer and a mobile information terminal such as mobile phone are enhanced, their circuits are extremely speeded up.
When a clock is speeded up to more than 100 MHz, it becomes difficult to sufficiently control noise (high-frequency electromagnetic noise or high-frequency electric vibration) leaking out from LSI to power supply lines on a printed circuit board by using only a laminated ceramic capacitor or a three-terminal capacitor, so that a possibility of malfunction and poor reception due to increasing noise increases.
As a capacitor which can solve the above problem, the applicant of the present invention has already proposed a strip-line capacitor (for example, refer to Patent Document 1, Patent Document 2, and Patent Document 3).
FIG. 51 is a cross-sectional view of a strip-line capacitor disclosed in Patent Document 1, and FIG. 52 is a cross-sectional view taken along the line A-A of FIG. 51.
As shown in FIGS. 51 and 52, a dielectric film 20 made of an oxide is formed on a surface of a metal plate 10 made of aluminum.
An electrically conductive polymer layer 31, an electrically conductive carbon paste layer 32, and a silver paste layer 33 are formed on the dielectric film 20.
An electrically conductive material layer 30 is formed by the electrically conductive polymer layer 31, the electrically conductive carbon paste layer 32, and the silver paste layer 33.
Positive electrode lead terminals 11 and 12 are connected to both longitudinal ends of the metal plate 10. A metal plate 40 made of a copper foil is arranged on one side surface of the electrically conductive material layer 30, and both longitudinal ends of the metal plate 40 are negative electrode lead terminals 41 and 42.
In addition, a filter constituting a transmission line type component in a coaxial structure is disclosed in Patent Document 4.
FIG. 53 is a diagram showing a component disclosed in Patent Document 4, FIG. 53A is a perspective view of the transmission line type component 1, FIG. 53B is a cross-sectional view in a longitudinal direction of the transmission line type component 1, and FIG. 53C is a cross-sectional view taken along the line E-E of FIG. 53B. As shown in FIGS. 53A to 53C, a coaxial line is constituted by arranging a high-dielectric insulating material 4 covering a signal conductor 2 which is a cylindrical internal conductor elongated in an axial direction, and a ground conductor 3 which is a cylindrical external conductor covering the high-dielectric insulating material 4. In order to easily mount this component on a printed circuit board, the signal conductor 2 of the internal conductor is pulled out to the outside of the high-dielectric insulating material 4.
In addition, a capacitor technology for realizing a nonpolar capacitor is disclosed in Patent Document 5.
FIG. 54 is a cross-sectional view of a technology disclosed in Patent Document 5.
An aluminum solid electrolytic capacitor 21 has solid electrolytic capacitor elements 22. Each of the solid electrolytic capacitor elements 22 includes an aluminum foil 23 which is a valve-acting metal on which an etching processing and a chemical conversion treatment for forming a dielectric film are performed. Each of the solid electrolytic capacitor elements 22 is formed by remaining an electrode lead part 25 in the aluminum foil 23, and impregnating an electrically conductive polymer 29 onto the aluminum foil 23 by being separated from the electrode lead part 25 by an insulating resin 27. A lead frame 31 is connected to the electrode lead part 25 of the solid electrolytic capacitor element 22.
By using two solid electrolytic capacitor elements 22, the two solid electrolytic capacitor elements 22 are arranged so that each electrode lead part 25 is placed in the opposite side to each other. The electrically conductive polymers 29 of the solid electrolytic capacitor elements 22 are joined to each other by using TCNQ complex (tetracyanoquinodimethane complex) 33.    Patent Document 1: Japanese Patent Application Laid-Open No. 2003-101311    Patent Document 2: Japanese Patent Application Laid-Open No. 2003-124066    Patent Document 3: Japanese Patent Application Laid-Open No. 2005-033813    Patent Document 4: Japanese Patent Application Laid-Open No. 2002-335107    Patent Document 5: Japanese Patent Application Laid-Open No. 2002-359169